Endoscopes are used by physicians to inspect and occasionally perform medical procedures within a body space in a patient such as a lumen or cavity. Generally, an endoscope has an elongated tube which carries a viewing system, such as a fiberoptic system, for viewing through the length of the endoscope. The distal end of the endoscope is first inserted into the patient's body space through a natural or surgical opening. The physician can then inspect that portion of the body space beyond the distal end by looking through coupling optics mounted on the proximal end of the endoscope.
Unfortunately, early endoscopes could not operate in opaque lumen fluids, such as blood in the blood vessels. To obviate this problem, inflatable balloons were placed circumferentially about the endoscope tube and inflated to seal the blood vessel. A clear flushing fluid such as saline is then introduced into the blood vessel to displace the blood and provide a clear view. However, even this approach has its shortcomings.
The viewing systems often fail because debris collects on the distal end of the system, obstructing the view. In addition, where the endoscope includes a laser light transmitting fiber, debris often becomes charred and bonded to the end of the fiber during use. Attempts to alleviate these problems by directing a flow of flushing fluid over the ends of the fiberoptic bundle and laser fiber have met with only limited success. As long as lumen fluid can come in contact with the ends of the viewing system or laser fiber, they can quickly be rendered inoperative.
Accordingly, it is desirable to provide an endoscopic device which avoids the difficulties of the prior art and provides unobstructed and continuous viewing within a patient's body space. It would also be desirable if such a device prevented debris collection on the end of the viewing system or laser light transmitting fiber. The present invention satisfies these desires.